Early Childhood Caries (ECC) is a burden worldwide which has a negative impact on children’s wellbeing and affects aesthetics, speech and mastication. It may lead to loss of space, creating problems that are difficult and expensive to manage in future. The International Association of Paediatric Dentistry (IAPD) declared that more than 600 million children worldwide are affected by ECC. Caries is a multifactorial disease and frequent excessive sugar consumption is noted as a major risk factor in the development of caries. It also contributes to other non-communicable diseases (NCDs) such as diabetes, obesity and cardiovascular disease. The well-established link between dental caries and dietary sugar, specifically sucrose, can be explained due to the fact that it can be fermented by microorganisms. The use of sugar substitutes may be justified as an effective way to prevent dental caries by modifying the metabolism of microorganisms which will lead to a reduction in lactic acid production in the mouth. This study explored the cariogenic potential of sugar substitutes. The aim of the study was to determine and compare the cariogenic potential of commercially available sugar substitutes namely: xylitol, erythritol and stevia. The data collected could be useful in finding a suitable substitute for sucrose, one of the main causative factors of ECC. A total of 52 enamel slabs were prepared from the surfaces of extracted primary teeth and placed in growth media before being inoculated with Streptococcus mutans (S. mutans). The enamel slabs and growth media were used to determine the Colony Forming Units (CFUs) of S. mutans after exposure to xylitol, erythritol and stevia and to determine the acid production of S. mutans in the presence of these sugar substitutes by measuring the acidity (pH) of the growth media. Biofilm formation in the presence of sucrose, xylitol, erythritol and stevia was confirmed by means of Scanning Electron Microscopy (SEM). Considering the CFUs, pH and SEM analysis, this study suggests that xylitol, erythritol and stevia are all less cariogenic alternatives to sucrose. Stevia has been shown to have the lowest cariogenic potential, followed by erythritol and then xylitol. These substitutes should however be used with caution as they still produced a drop in pH close to the critical demineralization level. From the literature studied, it is clear that ECC is a preventable disease. It is the dental professional’s duty to raise awareness with parents, caregivers, other health care professionals and all relevant stakeholders. Parents and patients should be educated to limit sugar intake and to substitute sugar with healthier alternatives such as xylitol, erythritol or stevia, which all proved to be less cariogenic than sucrose. / Dissertation (MSc Dent)--University of Pretoria, 2020. / Community Dentistry / MSc Dent / Unrestricted